drivers/scsi/ufs/ufs_bsg.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * bsg endpoint that supports UPIUs
   4  *
   5  * Copyright (C) 2018 Western Digital Corporation
   6  */
   7 #include "ufs_bsg.h"
   8
   9 static int ufs_bsg_get_query_desc_size(struct ufs_hba *hba, int *desc_len,
  10                                        struct utp_upiu_query *qr)
  11 {
  12         int desc_size = be16_to_cpu(qr->length);
  13         int desc_id = qr->idn;
  14
  15         if (desc_size <= 0)
  16                 return -EINVAL;
  17
  18         ufshcd_map_desc_id_to_length(hba, desc_id, desc_len);
  19         if (!*desc_len)
  20                 return -EINVAL;
  21
  22         *desc_len = min_t(int, *desc_len, desc_size);
  23
  24         return 0;
  25 }
  26
  27 static int ufs_bsg_verify_query_size(struct ufs_hba *hba,
  28                                      unsigned int request_len,
  29                                      unsigned int reply_len)
  30 {
  31         int min_req_len = sizeof(struct ufs_bsg_request);
  32         int min_rsp_len = sizeof(struct ufs_bsg_reply);
  33
  34         if (min_req_len > request_len || min_rsp_len > reply_len) {
  35                 dev_err(hba->dev, "not enough space assigned\n");
  36                 return -EINVAL;
  37         }
  38
  39         return 0;
  40 }
  41
  42 static int ufs_bsg_alloc_desc_buffer(struct ufs_hba *hba, struct bsg_job *job,
  43                                      uint8_t **desc_buff, int *desc_len,
  44                                      enum query_opcode desc_op)
  45 {
  46         struct ufs_bsg_request *bsg_request = job->request;
  47         struct utp_upiu_query *qr;
  48         u8 *descp;
  49
  50         if (desc_op != UPIU_QUERY_OPCODE_WRITE_DESC &&
  51             desc_op != UPIU_QUERY_OPCODE_READ_DESC)
  52                 goto out;
  53
  54         qr = &bsg_request->upiu_req.qr;
  55         if (ufs_bsg_get_query_desc_size(hba, desc_len, qr)) {
  56                 dev_err(hba->dev, "Illegal desc size\n");
  57                 return -EINVAL;
  58         }
  59
  60         if (*desc_len > job->request_payload.payload_len) {
  61                 dev_err(hba->dev, "Illegal desc size\n");
  62                 return -EINVAL;
  63         }
  64
  65         descp = kzalloc(*desc_len, GFP_KERNEL);
  66         if (!descp)
  67                 return -ENOMEM;
  68
  69         if (desc_op == UPIU_QUERY_OPCODE_WRITE_DESC)
  70                 sg_copy_to_buffer(job->request_payload.sg_list,
  71                                   job->request_payload.sg_cnt, descp,
  72                                   *desc_len);
  73
  74         *desc_buff = descp;
  75
  76 out:
  77         return 0;
  78 }
  79
  80 static int ufs_bsg_request(struct bsg_job *job)
  81 {
  82         struct ufs_bsg_request *bsg_request = job->request;
  83         struct ufs_bsg_reply *bsg_reply = job->reply;
  84         struct ufs_hba *hba = shost_priv(dev_to_shost(job->dev->parent));
  85         unsigned int req_len = job->request_len;
  86         unsigned int reply_len = job->reply_len;
  87         struct uic_command uc = {};
  88         int msgcode;
  89         uint8_t *desc_buff = NULL;
  90         int desc_len = 0;
  91         enum query_opcode desc_op = UPIU_QUERY_OPCODE_NOP;
  92         int ret;
  93
  94         ret = ufs_bsg_verify_query_size(hba, req_len, reply_len);
  95         if (ret)
  96                 goto out;
  97
  98         bsg_reply->reply_payload_rcv_len = 0;
  99
 100         pm_runtime_get_sync(hba->dev);
 101
 102         msgcode = bsg_request->msgcode;
 103         switch (msgcode) {
 104         case UPIU_TRANSACTION_QUERY_REQ:
 105                 desc_op = bsg_request->upiu_req.qr.opcode;
 106                 ret = ufs_bsg_alloc_desc_buffer(hba, job, &desc_buff,
 107                                                 &desc_len, desc_op);
 108                 if (ret) {
 109                         pm_runtime_put_sync(hba->dev);
 110                         goto out;
 111                 }
 112
 113                 fallthrough;
 114         case UPIU_TRANSACTION_NOP_OUT:
 115         case UPIU_TRANSACTION_TASK_REQ:
 116                 ret = ufshcd_exec_raw_upiu_cmd(hba, &bsg_request->upiu_req,
 117                                                &bsg_reply->upiu_rsp, msgcode,
 118                                                desc_buff, &desc_len, desc_op);
 119                 if (ret)
 120                         dev_err(hba->dev,
 121                                 "exe raw upiu: error code %d\n", ret);
 122
 123                 break;
 124         case UPIU_TRANSACTION_UIC_CMD:
 125                 memcpy(&uc, &bsg_request->upiu_req.uc, UIC_CMD_SIZE);
 126                 ret = ufshcd_send_uic_cmd(hba, &uc);
 127                 if (ret)
 128                         dev_err(hba->dev,
 129                                 "send uic cmd: error code %d\n", ret);
 130
 131                 memcpy(&bsg_reply->upiu_rsp.uc, &uc, UIC_CMD_SIZE);
 132
 133                 break;
 134         default:
 135                 ret = -ENOTSUPP;
 136                 dev_err(hba->dev, "unsupported msgcode 0x%x\n", msgcode);
 137
 138                 break;
 139         }
 140
 141         pm_runtime_put_sync(hba->dev);
 142
 143         if (!desc_buff)
 144                 goto out;
 145
 146         if (desc_op == UPIU_QUERY_OPCODE_READ_DESC && desc_len)
 147                 bsg_reply->reply_payload_rcv_len =
 148                         sg_copy_from_buffer(job->request_payload.sg_list,
 149                                             job->request_payload.sg_cnt,
 150                                             desc_buff, desc_len);
 151
 152         kfree(desc_buff);
 153
 154 out:
 155         bsg_reply->result = ret;
 156         job->reply_len = sizeof(struct ufs_bsg_reply);
 157         /* complete the job here only if no error */
 158         if (ret == 0)
 159                 bsg_job_done(job, ret, bsg_reply->reply_payload_rcv_len);
 160
 161         return ret;
 162 }
 163
 164 /**
 165  * ufs_bsg_remove - detach and remove the added ufs-bsg node
 166  * @hba: per adapter object
 167  *
 168  * Should be called when unloading the driver.
 169  */
 170 void ufs_bsg_remove(struct ufs_hba *hba)
 171 {
 172         struct device *bsg_dev = &hba->bsg_dev;
 173
 174         if (!hba->bsg_queue)
 175                 return;
 176
 177         bsg_remove_queue(hba->bsg_queue);
 178
 179         device_del(bsg_dev);
 180         put_device(bsg_dev);
 181 }
 182
 183 static inline void ufs_bsg_node_release(struct device *dev)
 184 {
 185         put_device(dev->parent);
 186 }
 187
 188 /**
 189  * ufs_bsg_probe - Add ufs bsg device node
 190  * @hba: per adapter object
 191  *
 192  * Called during initial loading of the driver, and before scsi_scan_host.
 193  */
 194 int ufs_bsg_probe(struct ufs_hba *hba)
 195 {
 196         struct device *bsg_dev = &hba->bsg_dev;
 197         struct Scsi_Host *shost = hba->host;
 198         struct device *parent = &shost->shost_gendev;
 199         struct request_queue *q;
 200         int ret;
 201
 202         device_initialize(bsg_dev);
 203
 204         bsg_dev->parent = get_device(parent);
 205         bsg_dev->release = ufs_bsg_node_release;
 206
 207         dev_set_name(bsg_dev, "ufs-bsg%u", shost->host_no);
 208
 209         ret = device_add(bsg_dev);
 210         if (ret)
 211                 goto out;
 212
 213         q = bsg_setup_queue(bsg_dev, dev_name(bsg_dev), ufs_bsg_request, NULL, 0);
 214         if (IS_ERR(q)) {
 215                 ret = PTR_ERR(q);
 216                 goto out;
 217         }
 218
 219         hba->bsg_queue = q;
 220
 221         return 0;
 222
 223 out:
 224         dev_err(bsg_dev, "fail to initialize a bsg dev %d\n", shost->host_no);
 225         put_device(bsg_dev);
 226         return ret;
 227 }